title: Determination of the antiretroviral drug tenofovir in plasma from HIV-infected adults by ultrafast isotope dilution MALDI-triple quadrupole tandem mass spectrometry.
abstract: A new and reliable mass spectrometric method using an isotope dilution method in combination with matrix-assisted laser desorption/ionization-triple quadrupole tandem mass spectrometry (ID-MALDI-QqQ-MS/MS) has been developed and validated for the determination of concentrations of the antiretroviral drug tenofovir (TNV) in plasma from HIV-infected adults. The advantage of this new method is that (1) the method is ultrafast and (2) can be applied for high-throughput measurement of TNV in plasma. The method is based on a simple plasma deproteinization step in combination with the use of [adenine-(13) C(5) ]-TNV as the internal standard. TNV and [adenine-(13) C(5) ]-TNV were monitored by multiple reaction monitoring using the transition m/z 288.0 → 176.2 and m/z 293.2 → 181.2 for TNV and [adenine-(13) C(5) ]-TNV, respectively. The method was validated according to the most recent FDA guidelines for the development and validation of (new) bio-analytical assays. Validated method parameters were: linearity, accuracy, precision and stability of the method. The lowest limit of quantification was 0.10 µmol/l, whereas the limit of detection determined at a signal-to-noise ratio (S/N = 3:1) in pooled drug free human control plasma was 0.04 µmol/l. The validated method was successfully applied and tested for its clinical feasibility by the analysis of plasma samples from selected HIV-infected adults receiving the prodrug tenofovir disoproxil fumarate. Observed plasma TNV concentrations ranged between 0.11 and 0.76 µmol/l and measured plasma TNV concentrations were within the therapeutically relevant concentration range.
authors.affiliation: Laboratory of Neuro-Oncology and Clinical and Cancer Proteomics, Department of Neurology, University Medical Center Rotterdam, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands. r.meesters@erasmusmc.nl
authors.forename: Roland J W
authors.initials: RJ
authors.lastname: Meesters
authors.forename: Jeroen J A
authors.initials: JJ
authors.lastname: van Kampen
authors.forename: Rachel D
authors.initials: RD
authors.lastname: Scheuer
authors.forename: Marchina E
authors.initials: ME
authors.lastname: van der Ende
authors.forename: Rob A
authors.initials: RA
authors.lastname: Gruters
authors.forename: Theo M
authors.initials: TM
authors.lastname: Luider
mesh_terms: D000225:Adenine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000737:chemistry; D000328:Adult; D019380:Anti-HIV Agents / Q000097:blood* / Q000737:chemistry; D015658:HIV Infections / Q000097:blood* / Q000188:drug therapy*; D006801:Humans; D007553:Isotope Labeling / Q000379:methods; D016014:Linear Models; D063065:Organophosphonates / Q000008:administration & dosage / Q000097:blood* / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods; D000068698:Tenofovir; D014280:Triglycerides / Q000097:blood
chemical_list: D019380:Anti-HIV Agents; D063065:Organophosphonates; D014280:Triglycerides; D000068698:Tenofovir; D000225:Adenine